The field of processing fruit and vegetables and the like, particularly grading, sorting and packing, has become increasingly automated in recent years as labor costs have risen and processing problems have been identified. Systems and apparatus are known, for example, for sorting fruit and the like as a function of weight, color, or color and weight. See U.S. Pat. No. 4,106,628, assigned to the same assignee. Likewise, other devices have been disclosed in the patent literature for sorting items as a function of size, blemish, grade, and various combinations of the above factors. However, the equipment that is available to the industry remains limited in the functions that can be performed, and in the efficiency and reliability of the apparatus in performing those functions. For example, in much of the previously available equipment, sensors or detectors generate only a limited amount of data concerning one or more conditions of the item being processed, and the apparatus lacks capacity to process intelligently on the basis of relatively complete information. For the processing and sorting of fruit such as citrus, and particularly for sorting as a function of surface blemish of fruit, it is highly desirable to maximize the amount of information collected concerning the surface condition of the fruit and to efficiently utilize that data in making sorting decisions. However, to achieve these general objectives, it is necessary to provide improvements both in the area of transducers, or sensors for acquiring the information, and in the capacity of the apparatus to efficiently process the acquired information so as to make accurate sorting decisions. The present invention provides such improvements.
For apparatus sorting on the basis of blemish or culls, it becomes very important to substantially uniformly illuminate the object which is to be viewed, and to make substantially all surface portions of the item available for viewing. Further, in development of the apparatus of this invention, it has been determined that it is advantageous to have a system and method whereby the data representative of the surface condition of the item is batch analyzed, i.e. all of the data corresponding to the item is analyzed after it has been acquired, as compared to performing the analysis as the data is being serially acquired. In prior art devices where analysis is performed concurrently with data acquisition, assumptions must be made as to the nature of the data being received from each item, so as to permit data processing in accordance with some predetermined function. This procedure is basically inflexible, and prohibits programming so as to alter the data processing as a function of the received data.
In connection with this invention, it has been determined that greater flexibility and reliability of data processing of large amounts of data can be achieved by batch data processing of the data corresponding to each item, as opposed to the prior art mode of serial processing. Further, the provision of substantially uniform illumination of the fruit or other item being inspected, as well as means for moving the item relatively so that all portions thereof can be examined, enables more accurate and reliable determinations of characteristics such as color, blemish, size and shape.